From what I have read, Mass does not institute their salt water license until 2011. They are using the Federal Registry for 2010. Your best bet right now is to contact the Mass Environmental Police and see what their stance is on it.
http://www.mass.gov/dfwele/dle/
http://www.mass.gov/dfwele/dle/contactus.htm

From the Mass FAQ page:
Q16. I am not a Massachusetts resident, but I often come to Massachusetts to fish for saltwater species. I have a recreational saltwater permit from my home state. Do I need another permit from Massachusetts?

A16. That depends. If the state you reside in recognizes the Massachusetts permit as a valid permit for recreational fishing in their waters, then Massachusetts would afford the same privileges to properly permitted individuals from that state. However, if your state of residence does not accept a valid Massachusetts permit for recreational fishing in their waters, than you would be required to purchase a Massachusetts permit to recreationally fish/land in Massachusetts.
http://www.mass.gov/dfwele/dmf/recreationalfishing/rec_license.htm#faq

From the CT FAQ page:

What is a reciprocal license privilege? (Is there reciprocity with any other states?)
Connecticut law allows non-resident anglers who hold a marine waters fishing license in New York, Rhode Island, Massachusetts, New Hampshire or Maine to fish in the marine district and land marine fish in this state without a Connecticut license provided the state issuing the marine license affords the same privilege to resident Connecticut marine license holders.


Can I fish in federal waters or in another state’s waters with a Connecticut Marine Waters license?

Federal waters: Federal registration is not required until January 1, 2010. Thereafter, CT Marine Waters fishing license holders will be exempt from the federal registry requirement. The CT Marine Waters Fishing License law was crafted to meet the federal criteria necessary to exempt our license holders from the federal registry.

New York: A saltwater license is not required for New York waters until October 1, 2009. Thereafter, New York will permit CT Marine Waters license holders to fish in the waters of Long Island Sound lying between NY and CT. Reciprocal privileges in other New York waters (ex. Block Island Sound) still need to be determined by New York officials.

NH: A saltwater license is not required for New Hampshire waters until January 1, 2011. There is no reciprocity with CT.

RI, MA, ME do not have marine license laws yet, so it is not possible to provide an answer for these waters. We will update this page as information becomes available for each state.